De Villiers will leave the post after instigating a series of changes since taking over the men's tennis tour in June 2005, including the introduction of the Hawkeye system of judging line calls, a reshuffle of the tour calendar and increased prize money.
The ATP said Thursday that the changes had been the most extensive in its 18-year history.
"I believe we have delivered the biggest modernization of the ATP Tour since its inception, have attracted unprecedented levels of investment into men's tennis and have begun to feed the growing appetite for men's tennis globally, both in established and emerging markets,'' De Villiers said. "I am honored to have played a part in taking our great sport to the next level.
"Now that this much needed change has been realized I believe this is the right time for someone new to build on this strong platform.''
The ATP said De Villiers will help in the search for his successor.
De Villiers, a former president of Walt Disney Television International, joined the ATP as chairman and became executive chairman and president five months later. He helped secure US$1 billion of new investment into the ATP Tour. Much was spent overhauling the tour's image to make it more fan friendly.
He also introduced byes for seeded players at Masters tournaments, which led to more appearances by the top players and the first increases in prize money for more than five years.
U.S. Open prize money to top $20 million for 1st time
HARRINGTON CLAIMS TOUR PRIZE
